In recent years, organic electroluminescent display devices have drawn attention as a next generation flat display device. The organic electroluminescent display device has excellent characteristics, including a light-emitting property, a wide viewing angle, and high-speed response. An organic electroluminescent element includes, by way of example, an organic layer, and a reflecting electrode with a low work function which are formed over a glass substrate. The organic layer includes a transparent electrode made of ITO or the like, a hole transport layer, an electroluminescent layer, an electron transport layer, and the like. An emitted light passes through the electrode and is taken out of a back surface of the substrate.
The organic electroluminescent display devices can have achieved high efficiency and a long lifetime by forming each organic layer by a vacuum deposition method. For example, R. Meerheim et. al discloses in a non-patent document 1 that a red organic electroluminescent element can be fabricated by the vacuum deposition method so as to have a half-life period of brightness of one and a half million hours or more at an initial brightness of 500 cd/m2.
On the other hand, a method for fabricating an organic electroluminescent display device without using the vacuum deposition method includes formation of an organic layer by a spin coat method, or by an ink jet method. The formation of the organic layer using a printing method, such as the ink jet method, can eliminate the necessity of an metal mask required for formation of the organic layer using the vapor deposition method. Thus, the organic electroluminescent display device can be fabricated more easily.
Such an organic electroluminescent display device fabricated by a wet process has short lifetime and efficiency as compared to the organic electroluminescent element formed by the vacuum deposition method. Non-patent Document 2 discloses that a red organic electroluminescent element fabricated using polymer material by the spin coat method has a lifetime of about a hundred thousand hours at an initial brightness of 500 cd/m2.
The organic electroluminescent element has a multilayer laminated structure. As a method for forming the multilayer laminated structure every pixel using a solution, Patent Document 1 discloses a method using a water repellent bank. This method forms a film in a pixel in such a manner that the solution is not formed on the bank by making the surface of the bank layer water repellent. Then, the water repellency of the bank surface is not eliminated by a drying process under inert atmosphere during a film formation process, so that the film formation process can be continuously performed without disturbing the position of formation of the film.    Patent Document 1: JP-A-2007-95512    Non-Patent Document 1: Appl. Phys. Lett., 89, 061111 (2006)    Non-Patent Document 2: IDW′ 06, p. 441 (2006)